Furnace shell construction



R. R. THOMAS FURNACE SHELL CONSTRUCTION May 13, 1952 Filed May 10, 1949 [mentor:

80360: E. 7740/ 145, ,mea ;od u

- region and in spaced relation thereirom.

Patented May 13, 1952 FUBNACE SHELL ONSTRUCTION lt'oscoe R. Thomas, Fairileld, Ala.asslgnor to United States Steel Company. a eorporation ol' New Jersey Application May 10, 1949, Serial No. 92.363

(c. ece-27 e 4 Claims.

This invention relates to improvements in turnace shell construetions. v

Blast turnaces and the like commonly have a refractory lining. an outer steel shell which sur rounds the lining, and a layer of insulating material between the shell and the lining. The upper portion oi' the shell supports the charging mechanism and consequently the shell must remain in aligmnent to prevent misalignment of the charging mechanism. The upper region oi the linin is subject to wear from abrasion of materials charged into the turnace and from the erosive eil'ect of gases. When the'lining in this region wears through, the insulating material falls away. The steel shell can withstand temperatures eneountered at the top of the furnace. but it tends to warp and thus to lose its alignment. g

An object of the present invention is to provide furnaces which embody improved shell constructions tor preventing warping of the outer shell comprises a series ot sockets s fixed to the interior of the outer shell and a series of lugs ll fixed to the adjacent face of the auxiliary shell and received in said sockets. The auxiliary shell 'extends around the full circumferenee `of the j for contraction and expansion. Closure strips i8 cover the spaces between the lining plates. These strips are welded to one of the plates adjacent in its upper region when the lining wears through.

A further object of the invention is to provide improved furnace shell constructions which embody an inner or auxiliary shell within the outer shell sparated'thererom by insulating material,` the auxiliary shell and the insulating material thua protecting the main shell against temperatures which cause it to warp. i

these and other obiects of the invention. I have provided improved details of structure. a preierred form of which is shown in the accomp drawing, in which:

e l. is a vertical sectional view of a furwhich an improved shell construetion em 4 g features ot the present invention;

2 is a horizontal sectional view taken substantialiy on line 11-11: of e i; and

3 d e are enlarged vertical and horizontai sectional views respectively illustrating the details oi the improved shell construction.

in the drawing there is shown the upper portion of a iurnace. such as a' metallurgical blast turnace. The furnace comprises a -efractory lining it. an outer shell &2 and a charging mecha- 53. all oi? which can be of suitable or dble construction. Aisc es known in the art, the space between the lining and the shell contains insulating material lt, such as expoliated vermieulite, granular diatomaceous earth. around reiractory or earth loam. or, preiormed type insulation, such as magnesia bl.

In accordaneewith the present invention, outer shell i! can-les an auxiliary shell it in its upper The each space and slidably contact the other plate. The lower end of the auxiliary shell preferably has an integral flange !9 which extends toward and preierably abuts the interier of the outer shell. The space between the two shells contains insulating material isa, which is similar to insulating material i& already described.

'During operation of the furnace, lining iii wears and. eventually wears through. Insulating material M falls away as soon as the lining is gone. At this stage the auxiliary shell, rather than the outer shell, becomes exposed to me temperatures prevalent in the upper regons of the furnace, which in iron ore blast furnaces are approximately 500 to 700 F. The steel shell can withstand such temperatures without falling, but it is likely to warp. such warping is connned to the auxiliary shell, since the layer of insulating material Ma maintains the outer shell at a sufllciently low temperature not to cause warping. Flange s on the auxiliary shell prevents loss of insulating material ita if the lining wears to this depth.

From the foregoing description it is seen that I have provided a simple construction and one which eectively prevehts warping of the outer sheh of urnacea The construction can be embodied readily in existing furnaces and overcomes the need for more elaborate means for this purpose, such as water sprays.

While I have shown and described only a single embodiment of the invention, it is apparent that modiflcations may arise. Therefore. I do not wish to be limited to the disclosure set forth but only by the sco'fe of the appended claims.

I claim:

1. In a urnace 'having a refractory lining. a metal outer shell surrounding said lining, and insulating material between said shell and said lining. an improved construction tor preventing warping of the outer shell in its upper region when said lining wears through comprising an auxiliary shell iormed of a series of arcuately preierred supporting means tor the anxiliary shell s spaced 'metal plates supported on the interier of said outer shell in its upper region and spaced therefrom, closure strips covering the spaces between adjacent plates and being fixed to one plate adjacent each space and slidably Contacting the other. and insulating material between said auxiliary shell and said outer shell. V

2. In a furnace having a rerractory lining, a metal outer shell surrounding said lining, and insulating material between said shell and said lining, an improved construction tor preventing warping oi the outer shell in its upper region when said lining wears through comprising an auxiiary shell iorned of a series of arcuately spaced metal plates supported on the interier oi said outer shell in its upper region and spaced theretrom. fianges on the lower edges o! said plates extending toward said outer shell, closure strlps covering the spaces between adjacent plates and being fixed to one plate a'djacent each space and slidably contacting the other, and insulating material between said auxiliary shell and said outer shell.

3. The combination with a blast furnace which includes an outer shell, a refractory lining spaced inside said outer shell, and charging mechanism at the top of the Iurnace carried by said outer shell of a device !or preventing warping of said outer shell in its upper region when said iining wears through comprising an auxiliary shell carries a flange extending toward said outer' shell for retaining said additional insulating material.

ROSCOE R. THOMAS.

REFERENCES CITED The following reierences are o! record in the file of this patent:

UNITED STATES PATENTB Number Name Date 287.204 Weimer Oct. 23, 1883 711.026 Updike Oct. 14, 1902 812,619 Timm Feb. 13. 1906 915,601 Hine. et al Mar. 16, 1909 936,308 Cook Oct. 12, 1909 1,674,947 Bunce June 26; 1928 1,703,5l7 D'ovei Feb. 26, 1929 1,847,710 Brassert et ai Mar. 1, 1932 2,283,163 Brassert etal May 19, 1942 2,486348 Wehr Oct. 25. 1949 

